Island



(No Model.)

G. W. STAFFORD & G. H. POLAND.

SHEDDING MECHANISM FOR LOOMS. No. 414,600. Patented Nov. 5, 1889.

WITNESSES:

UNITED STATES PATENT rricn,

GEORGE \V. STAFFORD AND CHARLES H. POLAND, OI PROVIDENCE, RIIODE ISLAND.

SHEDDING MEOHANlSM FOR LOOMS.

SPECIFICATION forming part of Letters Patent No. 414,600, dated November 5, 1889.

Application filed August 15, 1889.

To all whom it may concern:

Be it kn own that We, GEORGE IV. STAFFORD and CHARLES H. POLAND, of Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Shedding Mechanisms for Looms; and we do hereby declare that the following is a full, clear, and exact description thereof, reference being'had to the ac- IO companying drawings, and to the letters of reference marked thereon, which form a partof this specification.

This invention relates to that class of shedding mechanisms for looms known as dobbies.

The dobby form of shedding mechanism is to a considerable extent taking the place of the cam-andtreadle motion, because it is lighter and consequently admits of a higher rate of speed, and its capacity for readily producing a variety of patterns, though short of that of the jacquard, is still far in advance of that of the cam and treadle.

Dobbies are to a large extent being applied to looms already in use for plain work, because of their small cost and capacity for being readily changed from one pattern to ana other; and for the purpose ofapplying them to looms already in use it is necessary to accommodate them to the room already occupied by the loom. It has been found more advantageous for several reasons to place the dobby at the end of the loom rather than over it, Where the oil and dirt from the (lobby are liable to injure the work in the loom; but in putting the dobby on the end of the loom it has been found that the form of harnesslever heretofore frequently used in the dobby is too long and extends too far into the alley between the looms, and also makes it inconvenient to operate the pattern-chain.

The object of this invention is to obviate this difficulty, which is done by making use of a compound harness-lever composed of two simple levers connected and combined with the other parts of the dobby and with the harness-cording, as will hereinafter be explained.

The construction of a dobby constructed in accordance with our invention is illus seal No. 320,869. (No model.)

trated in the accompanying drawings, in which- Figure l-shows a vertical section of part of a loom and the dobby, and Fig. 2 shows a modification of the compound harness-lever.

In thedrawings, A is the end frame of the 100111, and B the frame of the dobby.

The harness-frame is designated by the letter h.

d a, is the cording connected with the top and bottom of the harness-frame and passing around sheaves '2 i on the loom-frame, as usual. The cording a is connected with the upper or free end of a lever G, pivoted at the loom side, as shown, while cording d is connected with the outer free end of a lever D, also pivoted at the loom side. The upper lever Gis held on a rod or shaft 0, located at the place where the usual lever is pivoted in ordinary dobbies, and the horizontal lever D is placed on a shaft 0 a little below the shaft of the lever O. In Fig. 1 the connection between the levers C and D consists of a segment or curved arm extending out from the lower end of the levers O and partially under and around the end of the lever D, the inside face of this curved arm being provided with gear-teeth g, which engage with similar teeth 3 made on the periphery of a segment on the under side of the lever D, so that when the lever G is moved the lever D will be moved through the medium of the gear-teeth, and if the pitchline of the gear-teeth is twice as far from the pivot of the lever C as it is from the pivot of the lever D the latter lever will have twice the angular motion that the lever G has, and consequently its free or outer end will need to be but half as long as the upper arm of lever O is in order to obtain the same extent of motion in operating the harness-frames.

The connection between the two levers C and D may be made as shown in Fig. 2, in which a link 2, pivoted at each end to the projecting lower ends of the levers, is used in place of the gear-teeth y to convey motion from one lever to the other. By connecting together the adjacent ends of the levers G and D, and causing the said ends to move together in the same direction, the two levers 1 c movement of the harness-frame, the said levers constituting a compound harness-lever.

My present construction enables me to shorten back the lower lever D to which the cord a, that draws down the harness-frame, is attached, far enough to allow the pattern-chain n to hang down freely. Moreover, it enables me to place the free or outer arm of said lever D in a position approximately horizontal, and to extend the cording therefrom in a substantially vertical line to the outer guidesheave '1), thereby obviating the well-known tendency of the cording to slacken when differences exist in the angles of the respective lengths extending from the guide-sheaves to the ends of the harness-lever.

A lever G, fast on the front end of the shaft (1, mounted in the dobby-frame, is connected at both its upper and lower ends by the rods 00' to the lifters r 7'', which in turn are connected by the rods 8 s to the depressors t 25. The lifters 7' r and the depressors t t slide in slots in the frame B. The rods 0 s and lever G have their counterparts on the other side of the dobby, so that both ends of the lifters and depressors are moved alike. j

A vertical jack-lever J is pivoted on the lever 0 and has a long hooked latch 70 7a pivoted to each end. These latches are made with hooks on the under sides of their free ends, which are so placed as to come over the lifters r 'r'. The plate-levers Z are placed over the pattern-cylinder D,.so as to be raised by the pins in pattern-chain n as they pass under the said levers, which levers operate the lower hook-latches by direct contact and the upper ones by means of the Wires m, to determine which shall be caught by the lifters r 1* and operate its jackdever and harness-lever 'to raise the harness-frame connected to it.

Having thus described our improvements,

what we claim as our invention is gether and in the same direction, said operating-connections being connected with the free ends of said levers, as described.

2. The combination, with a harness-frame and cording connected with the top and bottom thereof, of a compound harness -lever composed of two simple levers pivoted at the loom side and having their adjacent ends connected to move together in the same direction, whereby the said two levers are causedv to operate as one in effecting the movement of the harness-frame, said cording being con-.

nected with the free ends of said levers, and means connected with one of said levers for imparting movement thereto for effecting the movement of the harness-frame, all substantially as described.

4. The combination, with a harness-frame and cording connected with the top and bottom thereof, of a compound harness-lever composed of two simple levers pivoted at the loom side and having their adjacent ends connected to move together in the same direction, whereby the said two levers are caused.

to operate as one in effecting the movement of the harness-frame, said cording being connected with the free ends of said levers, a lehooked jacks pivoted to the opposite ends of said lever J, pattern devices for controlling the position of saidhooked jacks, and lifters and depressors operating in connection with said jacks and lever J, all as and for the purposes described.

GEO. w. STAFFORD. CHARLES H. POLAND.

\Vitnesscs:

WM. J. CHAPMAN, BENJ. ARNOLD,

5 ver J, pivoted to one of said simple levers, 

